Warning, /doc/phys_pkgs/darwin_cstore.rst is written in an unsupported language. File is not indexed.
view on githubraw file Latest commit 8916dab9 on 2022-03-21 14:59:06 UTC
8916dab93b Oliv*0001 .. include:: ../defs.hrst
0002
0003 .. _CarbonStore:
0004
0005 Internal carbon store and exudation
0006 '''''''''''''''''''''''''''''''''''
0007
0008 Note: the internal carbon store is currently only implemented for fixed
0009 plankton elemental ratios (i.e., :varlink:`DARWIN_ALLOW_NQUOTA`,
0010 :varlink:`DARWIN_ALLOW_PQUOTA`, :varlink:`DARWIN_ALLOW_FEQUOTA`,
0011 :varlink:`DARWIN_ALLOW_SIQUOTA` all undefined).
0012
0013 With :varlink:`DARWIN_ALLOW_CSTORE` defined, nutrient availability limits
0014 growth directly rather than via the photosynthesis rate. The maximum
0015 photosynthesis rate (and with it carbon uptake) becomes independent of
0016 nutritient limitation,
0017
0018 .. math::
0019
0020 P^{{\mathrm{C}}{\op{m}}}_j = P_{{\mathrm{C}},j}^{\max} f^{{{\text{phy}}}}_j(T) \gamma_{\op{pCO2}}
0021
0022 but the growth rate is limited by the availability of each nutrient,
0023
0024 .. math::
0025
0026 \mu_j = \min(P^{\op{C}}_j, \mu^{\max\op{N}}_j, \mu^{\max\op{P}}_j,
0027 \mu^{\max\op{Fe}}_j, \mu^{\max\op{Si}}_j)
0028
** Warning **
Wide character in print at /usr/local/share/lxr/source line 1030, <$git> line 30.
0029 Each nutrient’s availability determines a maximum achievable growth rate. Its
0030 form depends on whether variable quotas are enabled for the nutrient.
0031 For instance for phosphorus, without P quota,
0032
0033 .. math::
0034 :label: eq_darwin_max_growth_p
0035
0036 \mu^{\max\op{P}}_j = \frac{1}{R^{\op{P}:\op{C}}_j} V^{{\mathrm{P}}\max}_j
0037 \gamma^{\op{P}}_j f^{\op{up}}_j(T) ( 1 + r^{\op{resp}}_j )
0038
0039 and with P quota,
0040
0041 .. math::
0042 :label: eq_darwin_max_growth_p_noquota
0043
0044 \mu^{\max\op{P}}_j = \frac{1}{R^{\op{P}:\op{C}}_j} u^{\mathrm{P}}_j
0045 ( 1 + r^{\op{resp}}_j )
0046
0047 where :math:`u^{\mathrm{P}}_j` is the carbon-specific uptake rate for phosphorus,
0048
0049 .. math::
0050
0051 u^{\mathrm{P}}_j = V^{{\mathrm{P}}\max}_j \frac{\mathrm{PO}_4}{\mathrm{PO}_4 + k^{\op{PO4}}_j}
0052 {{\text{reg}}}^{Q{\mathrm{P}}}_j \cdot f^{{\text{up}}}_j(T)
0053
0054 and the respiration rate is
0055
0056 .. math::
0057
0058 r^{\op{resp}}_j = r^{\op{resp}\max}_j f^{\op{remin}}(T) \frac{c_j - c_j^{\min}}{c_j}
0059
0060 Other elements work analogously, except that the maximum nitrogen uptake rate
0061 for the case without nitrogen quotas is more complex,
0062
0063 .. math::
0064
0065 \mu^{\max\op{N}}_j = \frac{1}{R^{\op{P}:\op{C}}_j} u^{{\mathrm{N}}\max}_j
0066 ( 1 + r^{\op{resp}}_j )
0067
0068 where
0069
0070 .. math::
0071
0072 u^{{\mathrm{N}}\max}_j = \max( u^{{\mathrm{NO3}}\max}_j,
0073 u^{{\mathrm{NO2}}\max}_j, u^{{\mathrm{NH4}}\max}_j )
0074
0075 with
0076
0077 .. math::
0078
0079 u^{{\mathrm{N..}}\max}_j = V^{{\mathrm{N..}}\max}_j \gamma^{\op{N..}}_j
0080 f^{\op{up}}_j(T)
0081
0082 Part of the excess carbon is exuded to become DOC,
0083
0084 .. math::
0085
0086 E^{\op{C}}_j = (P^{\op{C}}_j - \mu_j) f^{\op{exude}}_j c_j
0087
0088 and part stored as fat,
0089
0090 .. math::
0091
0092 U^{\op{fat}}_j = (P^{\op{C}}_j - \mu_j) (1 - f^{\op{exude}}_j) c_j \;.
0093
0094 The Chlorophyll synthesis rate is based on the growth rate (as before).
0095
0096 .. csv-table:: Exudation parameters
0097 :delim: &
0098 :widths: 13,20,17,15,15,20
0099 :class: longtable
0100 :header: Trait, Param, Symbol, Default, Units, Description
0101
0102 :varlink:`FracExudeC` & :varlink:`a_FracExudeC` & :math:`f^{\op{exude}}_j` & 0.3 & & fraction of excess carbon exuded